How do I do it?

Follow the instructions below:

Copy the iCal URL from this page.http://www.whitby-astronomers.com/events/all/wdas_events.ics

In your Calendar program, look for a link to Add a new calendar by URL.

Paste the URL when asked, and you should be able to see WDAS events in your calendar. Depending on your Calendar, changes, cancellations and new events should be synchronised with this website calendar every few hours.